Transfer printing method

ABSTRACT

This invention provides a novel transfer printing method which comprises forming on an optional support a releasable layer composed of a composition comprising as main ingredients a resin and a solid solvent capable of being molten at elevated temperatures and dissolving said resin therein, forming on said releasable layer an optional pattern with an ink composition containing a dye having a dyeability to fibers to thereby obtain a transfer sheet, bringing a fibrous article into contact with the pattern-formed surface of the transfer sheet, heating the assembly under pressure to transfer the pattern on the fibrous article, subjecting the fibrous article to a dyeing treatment to thereby make the dye absorbed on fibers of the fibrous article, and then subjecting the fibrous article to a soaping treatment. According to this method, an optional pattern on the transfer sheet can be transferred on fibrous article without damaging properties, feeling and touch of the fibrous article and the transferred pattern can be dyed in a very clear and beautiful color. This effect is attained by a specific solid solvent to be combined with a resin in forming a releasable layer of the transfer sheet.

United States Patent iwi Mizuno l l TRANSFER PRINTING METHOD I75] Inventor: Shogo Mizuno. Toride. .lapan l73| Assignee; Dai Nippon Printing Company Limited. Tok u Japan [22] Filed: Feb. 12. I973 III I Appl. No.: 33|.347

{3U} Foreign Application Priority Data Oct W72 Japan. l r r r -17-llll4tll [ill LLS. Clt v 4 v r r v i, 8/2.5;427/2881417/l52 l5ll Int. CL" r r r v t r c 4 4 t r r .r D06P 5/00 [58} Field of Search 8/15. 117/364 38. 45

[56] References Cited UNlTED STATES PATENTS 1.993.513 NI Poschel a 8/25 lll ljhll ll/lfi! Cicogna..... 8/15 RUTNHIN 5119b: Cook r i r ll7/3fi.4

3il7(l t ll) 271965 Barboun. i r i ll7/3(1,4

3,45L5Xl 8/1969 Ne man r i i e i i i i i i. ll7/3h K 1.5nl99l 2/l97l Baum v v v v v v v ll7/3t'14 Irimur [Luz M ii: ier- Donald Levy Attorney. Agent. or FirmArmstrong Nikaido &

\Negncr N l Nov. 11.1975

[57] ABSTRACT This invention provides a no\el transfer printing method which comprises forming on an optional support a releasable la ver composed of a composition comprising as main ingredients a resin and a solid sol vent capable of being molten at elevated temperatures and dissolving said resin therein forming on said re leasable layer an optional pattern with an ink composition containing a the having a d eabilit to fibers to thereby obtain a transfer sheet. bringing a fibrous article into contact with the patterntormed surface of the transfer sheett heating the assembl under pressure to transfer the pattern on the fibrous article. subjecting the fibrous article to a (being treatment to thereh make the dye absorbed on fibers ol' the fibrous article. and then subjecting the fibrous article to a soaping treatment. According to this method. an optional pattern on the transfer sheet can he transferred on fibrous article \vithout damaging properties. feeling and touch of the fibrous article and the transferred pattern can he dyed in a very clear and beautiful color. This effect is attained by a specific solid sol\ent to be combined with a resin in forming a releasable layer of the transfer sheet.

1 Claim. 3 Drawing Figures US. Patent Nov. 11, 1975 3,918,895

TRANSFER PRINTING METHOD BACKGROUND OF THE lNVENTlON:

l. Field of the lnvention:

This invention relates to a transfer printing method for forming an optional colored pattern on woven fabrics, non-woven fabrics or knitted articles composed of fibrous materials such as natural fibers, regenerated fibers, semisynthetic fibers, synthetic fibers, etc.

2. Description of the Prior Arts:

Formation of optional colored patterns on fibrous articles such as mentioned above have heretofore been accomplished by printing methods, such as roll printing or screen printing methods, which comprise forming an optional pattern on a fibrous article with a printing agent comprising a dye or pigment by employing an intaglio formed by the engraving or etching method, by means of a roll or screen printing machine and subjecting the fibrous article to a dyeing treatment.

These conventional printing methods, however, include various problems and difficulties. For instance, it is very difficult to form an intaglio by the engraving or etching method, and hence, a formed pattern cannot but be simple one and selection of pattern is much limited. Further, since a printing agent is directly applied on a fibrous article with use of an intaglio or the like for formation of a pattern, a disadvantage that products of bad quality are frequently manufactured is inevitably brought about.

Moreover, in these conventional printing methods, a printing paste (or ink) is applied in a great thickness on a fibrous article, and therefore, it is very difficult to dry it sufficiently and it is hardly possible to conduct a multi-color printing according to such techniques. If a multi-color printing be possible, a dye or color printed in the latter stage is inhibited by a color paste printed in the preceding stage and the dyeing property of the latter printed dye or color is degraded. This is another defect of the conventional methods.

Recently, attempts were made to develop a method for forming an optional colored pattern on a fibrous article, which would overcome these defects of the conventional printing methods. For instance, there has been proposed and tried a transfer printing method comprising coating on an optional support a composition containing as the main ingredient a low-meltingpoint resin such as wax or rosin according to a customary procedure to form a releasable layer, printing an ink composition containing a dye or pigment on said releasable layer to thereby form a transfer sheet carrying an optional pattern thereon, bringing a fibrous article into contact with the pattem-formed surface of the transfer sheet, heating the assembly to transfer the pattern on the fibrous article, and subjecting the fibrous article to a dyeing treatment to obtain an optional colored pattern on the fibrous article.

Also such transfer printing method includes various problems and difficulties, and this transfer method is now utilized only for imparting a simple mark or pattern on a fibrous article and it is hardly practised on a commercial scale for forming optional colored patterns on fibrous articles.

The greatest cause for such difficulties and problems involved in this transfer printing method is that temperature conditions greatly differ among steps of the above transfer printing malthod and none of resin materials 2 satisfy sufficiently all of the temperature conditions differing among the steps.

More specifically, in the above transfer printing method, since a resin constituting the releasable layer, such as rosin or wax, has a low melting point, if only the heat transfer step is taken into consideration, use of such resin is very advantageous in that the heating temperature can be lowered. However, if the step of printing a pattern on the releasable layer is considered, use of such resin is defective in that since the releasable layer-constituting resin such as rosin or wax is molten or softened at the drying temperature of a printing machine or the like and the resin becomes viscous, it contaminates a guide roll of the printing machine and it adheres to subsequent printing rolls in the case of a multicolor printing, with the result that it is very difficult to obtain a beautiful multi-color pattern of a sharp distinction by the printing.

Still in addition, in case a releasable layer is constructed of such a low-melting-point resin such as rosin or wax, the above transfer printing method cannot obviate the following fatal defect. When the transfer printing is performed with use of an optional patterncarrying transfer sheet formed by employing an ink composition containing a dye, after the heat transfer treatment the fibrous article should inevitably be sub jected to a dyeing treatment to make the dye absorbed on the fibrous article. Such dyeing treatment is generally carried out at a temperature of about to C. Accordingly, at this treatment the low-melting-point resin, such as rosin or wax, of the releasable layer transferred onto the fibrous article is molten to disturb the pattern image on the fibrous article. As a result, it is impossible to impart a clear and beautiful colored pattern to the fibrous article, and furthermore, the melt of such low-melting-point resin penetrates into interiors of fibers of the fibrous article to damage drastically the touch or feeling of the fibrous article.

ln view of the foregoing, it may be considered to form a releasable layer by employing a high-melting-point resin instead of such a low-melting-point resin such as rosin or wax in the above transfer printing method. However, in this case there is brought about another disadvantage that the heat transfer step must be conducted at high temperatures and pressures so as to effect the transfer of such high-melting-point resin sufficiently.

Thus, if the heat transfer is performed at such high temperature and pressure, bad influences are imparted to a fibrous article to which the resin pattern is to be transferred. For instance, in the case of fibrous articles composed of synthetic fibers and similar fibrous materials, individual filaments or fibers constituting fibrous articles readily cause melt-adhesion under high temperature and pressure conditions adopted for the heat transfer, and in some cases they are converted to filmlike materials, resulting in drastic degradation of the touch and feeling of the fibrous articles. Further, even in the case of fibrous articles composed of natural fibers having relatively good then'nal properties, they are frequently colored into yellow or degraded in their mechanical properties when they are subjected to high temperature and pressure conditions for the heat transfer, with the result that their feeling and touch are drastically lowered and their commercial values are extremely reduced, and in especial cases, they cannot be applied to practical use at all.

SUMMARY OF THE INVENTION:

We have made extensive research works with a view to solving these problems included in the conventional transfer printing method and found that a very clear, delicate and beautiful colored pattern can be formed on a fibrous article without degrading physical properties, touch, feeling, etc. of the fibrous article, by coating on an optional support a composition containing as main ingredients a resin and a solid solvent, which is solid at room temperature but is capable of being molten at high temperatures and dissolving said resin therein, according to a customary method to thereby form a releasable layer on the support, forming on said releasable layer an optional pattern with an ink composition containing a dye having a dyeability to fibers to thereby obtain a transfer sheet, bring a fibrous article into contact with the pattern-formed surface of the transfer sheet, heating the assembly under pressure to transfer the pattern on the fibrous article, subjecting the fibrous article to a dyeing treatment to thereby make the dye adsorbed on fibers of the fibrous article and then subjecting the fibrous article to a soaping treatment. More specifically, it has been found that at the heat transfer step of the above procedures, the solid solvent is molten by an elevated temperature adopted for the heat transfer and it acts on the co-present resin to dissolve it therein or swell it, and hence, the strippability of the releasable layer can be heightened without increasing the temperature to a level exceeding the melting point of the resin, with the result that an optional pattern formed on the transfer sheet can be transferred conveniently and effectively on the fibrous article without causing such difficulties as encountered in the conventional transfer printing method. We have now completed this invention based on this finding.

In accordance with this invention, there is provided a transfer printing method which comprises forming on an optional support a releasable layer composed of a composition comprising as main ingredients a resin and a solid solvent which is solid at room temperature but is capable of being molten at elevated temperatures and dissolving said resin therein, forming on said releasable layer an optional pattern with an ink composition containing a dye having a dyeability to fibers to thereby obtain a transfer sheet, bringing a fibrous article into contact with the pattern-formed surface of the transfer sheet, heating the assembly under pressure to transfer the pattern on the fibrous article, subjecting the fibrous article to a dyeing treatment to thereby make the dye adsorbed on fibers of the fibrous article, and then subjecting the fibrous article to a soaping treatment.

DETAILED DESCRIPTION OF THE INVENTION:

The transfer printing method of this invention will now be illustrated by reference to accompaning drawings, in which FIGS. 1 and 2 are sectional view showing the structure of a transfer sheet to be used in the transfer printing method of this invention, and FIG. 3 is a sectional view showing the heat transfer step of the transfer printing method of this invention.

A composition (hereinafter referred to simply as releasing liquor") comprising as main ingredients a reisn and a solid solvent which is solid at room temperature but is capable of being molten at elevated temperatures and dissolving said resin therein (hereinafter referred to simply as solid solvent") is coated on an optional support 1 by a customary coating method such as rollcoating, gravurecoating and air knife-coating methods, so that the amount coated of the composition is about I to about 15 g/m (in the dry state), and the coated support is dried to form a releasing layer 2 on the support 1. Then, as is illustrated in FIG. 2, an ink composition containing a dye having a dyeability to fibers, i.e., an affinity with fibers, is applied on the releasable layer by a customary printing method such as gravure-printing, flexographic printing, ligthographic printing and screen-printing methods or by drawing with a brush or the like, to thereby form a monocolor or multi-color optional pattern 3 on the releasable layer 2. Thus is obtained a transfer sheet.

In the method of this invention, as illustrated in FIG. 3, a fibrous article 4 is brought into contact with the pattern-formed surface 3 of the transfer sheet and the assembly is heated under pressure, for instance, by passing it through between heating rolls 5 and 5', following which the support 1 of the transfer sheet is released off and the optional pattern 3 on the transfer sheet and a part or all of the releasable layer 2' are transferred onto the fibrous article 4.

In conducting the above heat treatment under pressure, it is possible to employ, instead of the heating rolls 5 and 5', a heated plate or heated iron (not shown) for pressing the transfer sheet.

Then, the fibrous article on which the optional pattern and a part or all of the releasable layer have been transferred from the transfer sheet is subjected to a dyeing treatment suitable for the dye contained in the pattern or fibers of the fibrous article according to customary procedures, and the fibers of the fibrous article are dyed with the dye contained in the patternv Then, the fibrous article is subjected to a soaping treatment sufficiently according to an ordinary method, whereby releasable layer, and an ink binder or excessive dye contained in the pattern are washed away, following which the fibrous article is dried. Thus is obtained a fibrous article having a very clear and beautiful pattern of a monocolor or multicolor.

As the optional support 1 to be used in the method of this invention, we can mention various papers, various films such as cellophane film, polypropylene film, polyester film, polyvinyl chloride film and polyamide film and metal foils such as aluminum foil. It is also possible to employ laminated films formed by laminating such papers or films according to a customary method.

It is proferred that the support 1 is composed of a material which is hardly affected by thermal conditions adopted in the pattern-forming step or the heat transfer step. In case a paper is used as the support in the method of this invention, it is preferable that it has such a high sizing degree as will hardly permit impregnation of the releasing liquor",

In this invention, a known thermoplastic high molecule material can be used as the resin component of the releasing liquor. Examples of the resin component to be used in this invention are natural resins such as copal, dammer, gum arabic, tragacanth gum, shellac, rosin, dextrin, starch and casein, rosin derivatives such as oxidized rosin and rosin esters, cellulose derivatives such as cotton nitrate, methyl cellulose, ethyl cellulose and carboxymethyl cellulose, hard resins such as lOO percent phenol resin, modified phenol resin, maleic acid resin, terpene resin, ketone resin and petroleum resin, vinyl resins such as polyvinyl chloride, polyvinyl acetate and vinyl chloride-vinyl acetate copolymers,

acrylic and methacrylic resins, polyethylene resins, polyvinyl alcohol resins, polyvinyl butyral resins, polyvinyl pyrrolidone resins, polyamide resins, polyester resins, urethane resins, and rubber derivatives. These resins can be used singly, or they can be used in the form of mixtures of two or more of them.

Any of substances can be used in this invention as the solid solvent" of the releasing liquor, insofar as they are solid at room temperature but are capable of being molten at elevated temperatures and dissolving the resin component therein. Specific examples of the solid solvent to be used in this invention include aromatic hydrocarbons such as naphthalene and its derivatives, diphenyl and its derivatives, stilbene, durene and phenanthrene; phenols such 2,3-dimethylphenol, 2,5- dimethylphenol, 3,4-dimethylphenol, 3,5-dimethylphenol, 2,4,6-trimethylphenol, 2,4,5-trimethylphenol, 3,4,5-trimethylphenol, catechol, resorcine, homocatechol, pyrogallol, a-naphthol and fi-naphthol; aromatic amines such as a-naphthylamine and triphenylamine, carboxylic acids such as o-toluic acid, m-toluic acid, malonic acid, glutaric acid, pimelic acid, azelaic acid and maleic acid; sulfonic acids such as benzene-sulfonic acid, p-toluene-sulfonic acid, naphthale-a-sulfonic acid and naphthalene-B-sulfonic acid; fatty acids such as beef tallow, stearic acid, and palmitic acid and metal salts of these fatty acids; anionic, cationic, nonionic and amphoteric surfactants; sugars such as fructose; and polyethylene glycol and chlorinated paraffin.

Solid solvents such as exemplified above take a definite liquid phase or solid phase with the melting point as a line of distinction. Thus, in this invention, the solid solvent retains the solid phase at a drying temperature adopted at the step for forming an optional pattern on the transfer sheet and does not dissolve the co-present resin component, whereas at the elevated temperature adopted at the heat transfer step it is molten and dissolves the co-present resincomponent therein. It is also desired that the solid solvent is not molten at the dyeing temperature adopted at the dyeing step as at the pattem-forming step and it does not dissolve the co-present resin. in view of these thermal conditions adopted at the steps of the method of this invention, it is preferred that the solid solvent" is solid at room temperature and has a melting point ranging from about 70C. to about l50C. and that it exhibits in the molten state a high power of dissolving the co-present resin therein.

Even if the dissolving power of the solid solvent in the molten state is not so high for the co-present resin component, if it can only swell the resin, s'uch solid solvent can be used in this invention.

In this invention, any of combinations of such resins as exemplified above with solid solvents such as examplified above may be utilized, but in view of various conditions adopted in conducting the method of this invention, it is preferred that combinations of the resin and solid solvent" meet the following requirements:

a. Neither the resin or the solid solvent is molten at a drying temperature adopted at the step for forming an optional pattern on the transfer sheet.

b. At a heating temperature adopted at the heat transfer step, the solid solvent is molten though the resin is not molten and the molten solid solvent" can dissolve the resin therein.

c. When the solid solvent" is molten at a heating temperature adopted at the heat transfer step, the

melt of the solid solvent" does not adversely affect a fibrous article piled on the transfer sheet.

d. Neither the resin or the solid solvent" is molten at an elevated temperature adopted at the dyeing treatment.

It is not necessarily required in this invention that all of the above requirements should be satisfied, but the method of this invention can be conducted sufficiently if at least one of the above requirements is satisfied. Especially good results can be obtained when the requirements (b) and (c) are satisfied. Therefore, it is important to select a combination of a resin and a solid solvent" meeting the requirements (b) and (c).

The composition to be used in this invention for forming releasable layer contains as main ingredients such resin and solid solvent" as mentioned above. It may further comprise, according to need, such additivies as plasticizers, fillers, driers and emulsifiers, and it may be employed in the form of an emulsion, a solution or a suspension prepared by incrorporation of water or an organic solvent.

in the above-mentioned pasty composition to be used in the method of this invention, the mixing ratio of the resin and the solid solvent is chosen appropriately depending on the object of the transfer, the kind of the pattern image, the kind of the fibrous article and the dyeing method.

As the ink composition containing a dye having dyeability to fibers, there may be employed, for instance, an ink composition prepared by adding a dye having a dyeability into an ordinary vehicle for an ink compositions, incorporated with such known additivies as plasticizers, waxes, greases, driers, assistant driers, fillers and emulsifiers optionally according to need, and kneading the resulting mixture sufficiently with use of a solvent or diluent.

in addition to the above-mentioned ink composition, it is also possible to employ a conposition formed by employing as main ingredients such resin and solid solvent" as used for forming a refeasable layer, adding thereto optionally such known additives as mentioned above, incorporating therein a dye having a dyeability to fibers, and kneading the resulting mixture with use of a solvent or diluent.

Known vehicles can be used as the vehicle of the ink composition to be employed in this invention, and examples of such vehicle include oils such as linseed oil, soybean oil and synthetic drying oils; natural resins and modified natural resins such as rosin, copal, dammer, hardened rosin, rosin ester and polymerized rosin; synthetic resins such as rosin-modified phenol resin, phenol resin, maleic acid resin, alkyd resin, petroleum resin, vinyl resin, acrylic resin, polyamide resin, epoxy resin and aminoalkyd resin; cellulose derivatives such as nitrocellulose and ethyl cellulose; rubber derivatives such as chlorinated rubber and cyclized rubber; and such substances as casein, glue, dextrin and zein.

Some of vehicles exemplified above are the same as resins to be used for forming a releasable layer.

Any of dyes having a dyeability to fibers mentioned hereinafter, i.e., an affinity with these fibers, may be used as the dye to be incorporated into the ink composition. For instance, acid dyes, acid mordant dyes, basic dyes, direct dyes, naphthol dyes, vat dyes, sulfur dyes, disperse dyes and reactive dyes can be optionally used. Chemically speaking, it is possible to employ in this invention, for instance, azo dyes, anthraquinone dyes, indigoid dyes, thioindigoid dyes, diphenylmethane dyes,

7 triphenylmethane dyes, phthalocyanine dyes, nitro dyes, nitroso dyes, thiazole dyes, xanthene dyes, acridine dyes, azine dyes, oxazine dyes, thiazine dyes and cyanine dyes.

Physical properties required for the ink composition vary depending on such factors as the kinds of the vehicle and dye used, the material of the fibrous article, the weaving or knitting manner of the fibrous article, conditions adopted at the pattern-forming heat transfer and dyeing step, and the structure of the pattern to be transferred. Accordingly, in this invention, it is desired to prepare an ink composition having physical properties deemed to be optimum in view of these factors.

In this invention it is preferred that an optional pattern formed with use of such ink composition is viscous and exhibits a necessary bit lowest adhesiveness to the fibrous article at the heat transfer step. The reduction of the cohesive force, such as effected in the releasing layer, is not preferred for the pattern, because such reduction of the cohesive force results in deformation of the pattern at the heat transfer step or subsequent dyeing step.

Fibrous articles composed of known fibers are used in this invention as the fibrous article onto which as optional pattern is transferred. For instance woven fabrics, non-woven fabrics, knitted articles and the like composed of such fibrous materials as vegetable fibers, e.g., cotton and flax; animal fibers, e.g., wool and silk, inorganic fibers, e.g., asbestos and glass fibers, regenerated artificial fibers, semi-synthetic fibers, e.g. acetate fibers and rayon fibers, and synthetic fibers, e.g., polyamide fibers; polyester fibers, polyurethane fibers, polypropylene fibers, polyvinyl chloride fibers, polyvinylidene chloride fibers, polyacrylonitrile fibers and polyvinyl alcohol fibers, are used.

Temperature and pressure conditions adopted at the step for heating an assembly of the heat transfer sheet and the fibrous article piles on the pattern-carrying surfurce of the transfer sheet vary depending on the trans fer speed and the thickness of the support of the transfer sheet, but it is always indispensable that the heating temperature should not increase the heat distortion temperature of the fibrous article. For instance, it is preferred that the heating temperature is l-l60C. in the case of a polyester fibrous article, 120l 50C. in the case of a nylon fibrous article, llOl40C. in the case of a vinylon fibrous article and l l0-l40C. in the case of a fibrous article of acrylonitrile fibers. In case the heating temperature exceeds such range, the touch of the fibrous article is extremely hardened. Therefore, adoption of too high a temperature should be preferably avoided.

In this invention, it is possible to heat the assembly of the transfer sheet and the fibrous article brought into contact with the pattem-carrying surface of the transfer sheet, prior to the heat transfer treatment, from the support side of the transfer sheet by means of such a heating device as an infrared heater, an electric heater and a hot roll.

In accordance with this invention, when the assembly of the transfer sheet and the fibrous article in contact with the pattem-carrying surface of the transfer sheet is heated under pressure under conditions such as men tioned above, the solid solvent" contained in the re leasable layer of the transfer sheet is molten and the melt of the solid solvent" acts on the resin co-present in the releasable layer and dissolves or swells said resin. Accordingly, it is made possible to heighten the strippa- 8 bility of the releasable layer without elevating the temperature up to the melting point of the resin and to transfer an optional pattern from the transfer sheet under mild conditions without disturbing the pattern image.

In this invention, in case a combination of the same resin and solid solvent as used for formation of the releasable layer is used as a vehicle of the ink composition, also in the pattern layer formed by such ink composition, the same phenomena as mentioned with respect to the releasable layer are caused to occur and the transferability of said pattern can be greatly hightened.

In this invention the dyeing treatment can be performed by a customary dyeing method, such as a steam treatment, a heating treatment, a chemical treatment and the like, though an optimum treatment varies depending on the kinds of the fibrous article and dye and other factors.

If an optional pattern is transferred on the fibrous article by the above heat transfer treatment, unless the subsequent dyeing treatment is conducted, the pattern is present on the fibrous article merely in the state contacted or sticked to the fibrous article and the fibrous article is not dyed with the dye contained in the trans ferred pattern. Accordingly, the dyeing treatment is carried out so as to fix and make adsorbed the dye of the pattern into the fibrous article.

In this invention, the soaping treatment can be accomplished by a customary washing method employing an aqueous solution containing a soap or detergent. in this invention, after the above-mentioned dyeing treatment, the soaping treatment is carried out in order to remove the releasable layer left on the fibrous article, the ink vehicle or excessive dye not adsorbed on the fibrous article, whereby the degree of absorption of the dye on the fiber can be heightened and the touch or feeling of the fibrous article can be greatly improved.

As is apparent from the foregoing description, the transfer printing method of this invention comprises forming on an optional support a releasable layer composed of a composition comprising as main ingredients a resin and a solid solvent which is solid at room temperture but is capable of being molten at elevated temperatures and dissolving said resin therein, forming on said releasable layer an optional pattern with an ink composition containing a dye having a dyeability to fibers to thereby obtain a transfer sheet, bringing a fibrous article into contact with the pattern-formed surface of the transfer sheet, heating the assembly under pressure to transfer the pattern on the fibrous article, subjecting the fibrous article to a dyeing treatment to thereby make the dye adsorbed on fibers of the fibrous article, and then subjecting the fibrous article to a soaping treatment.

In the transfer printing method if this invention various advantages are brough about by forming a releasable layer of the transfer sheet, and optionally a pattern to be transferred on the fibrous material, with a compo sition comprising as main ingredients a resin and a "solid solvent and optionally in ink composition comprising the same resin and solid solvent."

For instance, in case releasable layer is formed on a support and an optional pattern is then formed on the releasable layer, the releasable layer does not become viscous at a temperature adopted for forming said optional pattern and then drying it, with the result that a printing machine or the like is not contaminated and a transfer sheet having a very clear and beautiful pattern of a monocolor or multicolor can be formed.

Further, in this invention, when the fibrous article is brought into contact with the pattern-carrying surface of the transfer sheet and the assembly is heated under pressure to effect the transfer of the pattern, the solid solvent contained in the releasable layer of the transfer sheet is molten at an elevated temperature adopted for the transfer treatment and acts in the molten state on the co-present resin to dissolve or swell it. Accordingly, it is made possible to heighten the strippability of the releasable layer without elevating the temperature up to the melting point of the resin and to transfer an optional pattern from the transfer sheet onto the fibrous article under mild conditions without disturbing or deforming the pattern image, with the consequence that there is brought about another adavantage that the touch or feeling of the fibrous article is not damaged by the heat transfer treatment which can be accomplished under mild conditions, e.g., a relatively low heating temperature Still further, in this invention, the releasable layer transferred on the fibrous article is not influenced by elevated temperatures such as adopted at the dyeing treatment. Therefore, the touch or feeling of the fibrous article is not damaged by the presence of the releasable layer at the dyeing treatment because it does not permeate into the interior of the fiber article but can be washed away completely by the subsequent soaping treatment.

By dint of the above-mentioned excellent effect, this invention can provide a dyed article having a very clear, delicate and beautiful pattern excellent in dye fastness and having an excellent touch or feeling.

The invention will now be illustrated by reference to examples, in which all of the parts are on the weight basis.

EXAMPLE 1 A solution consisting of 30 parts of a rosin-modified maleic acid resin, (having a softening point of l56165C. 20 parts of acetylsalicylic acid (having a melting point of 135C), 30 parts of ethanol and 40 parts of toluene was coated in an amount of 20 g/m uniformly on a glassine roll paper of B size and a unit weight of 53 Kg by means of a reverse roll coater, and was then dried at about 100C, to form a releasable layer.

A prescribed multi-color pattern was formed on the releasable layer by conducting a three-color circular printing with a photogravure of a maximum cell depth of 50 microns at 175 lines per inch at a drying temperature of about 110 to about 120C. with use of three inks, each consisting of parts of a disperse dye, 13 parts of ethyl cellulose, 3 part of heavy calcium carbonate, 1 part of maleic acid, 10 parts of ethanol, 10 parts of ethyl acetate and 50 parts of toluene. Thus was obtained a transfer sheet of the rolled state carrying a three-color pattern on the surface thereof. Since melting was not caused by the drying heat, guide rolls were not contaminated and the printing was carried out in good conditions without back trap at the overlap printing. Disperse dyes used for the above yellow, red and blue inks were Kayalon Polyester Light Yellow 6 GL- S(C.l. Disperse Yellow 109 A methine dye.) Red BL-SF Paste (C.l. Disperse Red 165, an anthraquinone dye) and Kayalon Polyester Turquoise Blue GL-SF (C.I. Disperse Blue 60, an azo dye), respectively.

The back surface of the transfer sheet was contacted with a roll heated at 1S0l55C. at a point about 2m before transfer rolls of a transfer machine in a manner such that the transfer sheet could have a contact with the heated roll at a great area, whereby the releasable layer and the inks were pre-heated.

A fabric composed of 100 percent polyester fibers having a unit weight of about 100 g/m was brought into contact with the printed surface of the transfer sheet, and the assembly was passed through a pair of transfer rolls maintained at 140C. at a rate of 8 m/min. Between the two transfer rolls, a pressure of about 200 kg/cm was imposed. Immediately after the passage through the transfer rolls, the transfer sheet was re leased off from the polyester fabric. A three-color overlapped printed image and the releasable layer were thus transferred on the polyester fabric. The ink transfer ratio was more than 99 percent. The polyester fabric on which the printed image had been transferred was steam-heated at 120C. by means of a steamer for 30 minutes to make the dyes adsorbed on fibers of the polyester fabric. No disturbance was caused on the printed image by this steam heating treatment. Then, the polyester fabric was soaped with a wince soaper maintained at 50C and containg 5 g/ I of Monogen and 3 g/l of NaOH, to thereby remove the releasable layer, inks, binder, excessive dyes and insufficiently fixed dyes from the polyester fabric. Thus was obtained a polyester fabric having a delicate and beautiful, multicolor-printed pattern and a good touch.

EXAMPLE 2 Procedures of Example 1 were repeated in the same manner except that the pre-heating of the transfer sheet was not effected. The heat transfer and subsequent steps could be conducted conveniently and similar results were obtained.

EXAMPLE 3 A solution consisting of 50 parts of a polyamide resin, 5 parts of polyethylene glycol having a melting point of about C. 3 parts of ethylcellulose and 50 parts of toluene was coated in an amount of 5 g/m uniformly on a casein-undercoated kraft roll paper by a gravurecoating method, to form a releasable layer on the kraft paper.

A pattern of waterdrop-like spots was formed on the releasable layer by the circular printing method using a flexographic pringint machine with use of two inks, each consiting of 10 parts of a reactive dye, 15 parts of polyvinyl butyral, 2 parts of sorbitan fatty acid ester, 5 parts of finely divided silica, 30 parts of ethanol and 30 parts of isopropyl alcohol. The reactive dyes used were Procion Brilliant Green H-4G (C.1. Reactive Green 5, a phthalocyanine dye) for the green ink and Procion Turquoise H-A (C.l. Reactive Blue 71; a phthalocyamine dye) for the blue ink. Thus was obtained a transfer sheet.

A satin fabric of percent cotton was brought into contact with the printed surface of the transfer sheet, and the assembly was passed at a rate of 5 m/min through calender rolls heated at C. lmmedaitely after the passage through the calender rolls the support of the transfer sheet was released off from the cotton fabric. Thus, the printed pattern of water-drop-like spots was beautifully transfered into the cotton fabric surface.

The pattern-transferred cotton fabric was dipped in a dye-fixing agent consisting of 150 parts of sodium carbonate, 100 parts of sodium chloride, 50 parts of potassium carbonate. 10 parts of sodium metasilicate, 27 parts of sodium hydroxide and 700 parts of water and was allowed to stand still at room temperature for about 24 hours, whereby reactive dyes contained in the inks were allowed to react with cotton fibers and were adsorbed therein. Then, the cotton fabric was washed with water by means of a wince soaper. Thus was obtained a cotton fabric having a beautiful pattern of green and blue round spots and having a good touch.

EXAMPLE 4 A solution consisting of 5 parts of polyvinyl alcohol, 15 parts of resorcin having a melting point of 110C., parts of triphenylamine having a melting point of 127C 20 parts of ethanol, 1 parts of octyl alcohol and 80 parts of water was coated in an amount of g/m uniformly on a glassine paper of a size B having a unit weight of 75 kg by means of an air knife coater. A fourcolor-overlapped printing was formed on the above releasable layer at a drying temperature of 80C. with use of a gravure on which a landscape photo isetched with a maximum depth of 60 microns at 150 lines per inch, to thereby form a transfer sheet. Each of four inks used consisted of 8 parts of an acid dye, 6 parts of polyvinyl alcohol, 1 part of polyethylene glycol laury ether, 10 parts of ethanol, 10 parts of isopropyl alcohol and 80 parts of water. Acid dyes used were Kayanol Milling Yellow 0 (CIA. Yellow 38)(C.1. 25125) for the yellow ink, Kayanol Red NBR (C.l. Acid Red 266) for the red ink, Kayanol Milling Ultrasky SE (C.l.A. Blue 112) for the blue ink and Kayanol Milling Black TLB (C.l.A. Black 109) for the black ink.

In the same manner as in Example 1, the back surface of the transfer sheet was contacted with a roll heated at 130C. at a point just before transfer rolls to thereby heat-melt the releasable layer and the ink compositions. Then, the transfer sheet combined with a nylon tricot fabric was passed through between a pair of transfer rolls heated at 110C. and immediately thereafter, the transfer sheet was released ofi from the nylon tricot fabric. Thus, a sharp landscape photo was transferred onto the nylon tricot fabric.

The nylon tricot fabric was steam-heated by a steamer maintained at 105C. for minutes to make the dyes absorbed in nylon fibers, and then the fabric was washed with a great quantity of flowing water and subjected to a soaping treatment with a soaping liquor maintained at 50C. and containing 3 g/l of Monogen by means of an open soaper to obtain a nylon tricot fabric having a printed landscape photo of a beautiful tint and a good touch.

EXAMPLE 5 Procedures of Example 4 were repeated on a silk fabric to obtain a printed silk fabric as excellent as the product obtained in Example 4.

EXAMPLE 6 In the same manner as in Example 3, a releasable layer was formed on a glassine paper of B size having a unit weight of 53 Kg. and a solution consisting of 1 parts of methyl cellulose, parts of beef tallow, 3 parts of Kayalon Fast Red R (C.1. Disperse Red l7)(C.1. 11210). 30 parts of ethyl alcohol, 30 parts of isopropyl alcohol and 30 parts of water was coated in 12 an amount of 30 g/m uniformly throughout the releasable layer according to the roll coating method to form a transfer sheet having an all-over printed pattern.

The pattern was transferred on an acetate velvet cloth at a transfer temperature of C. according to procedures as described in Example 1. Thus, a red ink pattern was transferred on the entire surface of the acetate velvet cloth.

The acetate velvet cloth was then steam-heated under atmospheric pressure for 20 minutes by means of a steamer maintained at C, which temperature was high than the melting point of the beef tallow used, to thereby make the dye adsorbed on fibers of the acetate velvet cloth. Then the acetate velvet cloth was washed with water and subjected to a soaping treatment with a soaping liquor containing 2 g/l of Monogen and 2 g/l of sodium carbonate by means of an open soaper maintained at 50C. to obtain a plain acetate velvet cloth colored entirely in red and having a good touch. Flocks had a length of about 2mm, and even the root portions of flocks were uniformly dyed without falling of flocks.

EXAMPLE 7 A solution consisting of 50 parts of Piccotex (manufactured by Esso Standard), 5 parts oof stearic acid, 3 parts of ethyl cellulose and 50 parts of toluene was coated in an amount of 5 g/m uniformly on a casein-undercoated kraft roll paper according to the gravure-coating method to form a releasable layer.

A two-colored pattern of water-drop-like spots was formed on the releasable layer by the circular printing method using a flexographic printing machine with use of two inks, each consisting of 10 parts of a reactive dye, 15 parts of polyvinyl butyral, 2 parts of sorbitan fattay acid ester, 5 parts of finely divided silica, 30 parts of ethanol and 30 parts of isopropyl alcohol, to thereby form a transfer sheet. Reactive dyes used were Procian Brilliant Green H-4G for the green ink and Procian Turkis H-A for the blue ink.

A satin fabric of 100 percent cotton was brought into contact with the printed surface of the transfer sheet, and the assembly was passed through between calender rolls heated at 110C. at a rate of 10 m/minv Immediately after the passage through the calender rolls, the support of the transfer sheet was released off from the cotton fabric. The pattern of water-drop-like spots was beautifully transferred on the cotton fabric.

The pattem-transferred cotton fabric was dipped in a dye-fixing agent consisting of parts of sodium carbonate, 100 parts of sodium chloride, 50 parts of potassium carbonate, 10 parts of sodium metasilieate, 27 parts of sodium hydroxide and 700 parts of water, and was allowed to stand still at room temperature for about 24 hours, whereby the reactive dyes in the ink were allowed to react with cotton fibers and were adsorbed therein. Then, the cotton fabric was washed with water by means of a wince soaper to obtain a cotton fabric having a beautiful pattern of round spots of green and blue colors and having a good touch.

What is claimed is:

1. In a transfer printing method wherein a releasable layer is formed on a support; a pattern of an ink composition containing adye having a dyeability to fibers is formed on the releasable layer thereby forming with the support and releasable layer a transfer sheet; the pattern-formed surface of the transfer sheet is brought into contact with a fibrous article; the assembly of the 14 able layer, a resin and a solid solvent which is solid at room temperature but is capable of being molten at elevated temperatures and dissolving said resin therein. said resin being a rosin-modified maleic acid resin and said solid solvent being a acetylsalicylic acid. 

1. IN A TRANSFER PRINTING METHOD WHEREIN A RELEASABLE LAYER IS FORMED ON A SUPPORT, A PATTERN OF AN INK COMPOSITION CONTAINING ADYE HAVING A DYEABILITY TO FIBERS IS FORMED ON THE RELEASABLE LAYER THEREBY FORMED WITH THE SUPPORT AND RELEASABLE LAYER A TRANSFER SHEET, THE PATTERN FORMED SURFACE ON THE TRANSFER SHEET IS BROUGHT INTO CONTACT WITH A FIBROUS ARTICLE THE ASSEMBLY OF THE TRANSFER SHEET AND FIBROUS ARTICLE IS PRESSED OR HEATED TO TRANSFER THE PATTERN TO THE FIBROUS ARTICLE, THE FIRBOU ARTICLE IS SUBJECTED TO A DYEING TREATMENT TO CAUSE THE DYE OF THE INK COMPOSITION TO ABSORBS TO FIBERS OF THE FIBROUS ARTICLE AND THE FIBROUS ARTICLE IS THEREAFTER SUBJECTED TO A SOAPING TREATMENT, THE IMPROVEMENT COMPRISING EMPLOYING AS THE MAIN INGREDIANTS OF THE RELEASABLE LAYER, A RESIN AND A SOLID SOLVENT WHICH IS SOLID AT ROOM TEMPERATURE BUT IS CAPABLE OF BEING MOLTEN AT ELEVATED TEMPERATURES AND DISSOLVING SAID RESIN THEREIN, SAID RESIN BEING A ROSIN-MODIFIED MALEIC ACID RESIN AND SAID SOLID SOLVENT BEING A ACETYLSALICYLIC ACID. 